STEAM TRACINGS

[ulpian]

Hi,

We are using 3/8 copper tubings for steam tracings our phenol and other pipelines at 65 psig pressure with 0 psig back-pressure.
In our steam trap strainers we get a brown fine powder (may be some oxide?) and that causes lots of trouble.
Any ideas what this powder may be and how to get rid of this? Can this cause excessive pressure drop in the tracings?

 

[roker]

Hi,
If you have carbon steel components in the piping so with the copper and hot water you get a galvanic cell and the powder is the corrosion product, we are using carbon steel tubes for steam tracing.

roker

 

[TBP]

I'd see if the brown powder is copper. Condensate in copper can sometimes (not always, but sometimes) can cause problems like this. (Very bad news if copper gets back into a boiler. It WILL set up a cell there, and cause pitting very similar to oxygen corrosion.) I know of one large plant that had copper build-up on the TD traps they used on tracing service. This caused the traps to blow through. They blamed the manufacturer, and went with another make of traps. The same thing happened again. The last I heard, they had actually come to accept that the deposits were copper, and were replacing the copper tracing lines with SS tubing.

AS for pressure the pressure drops, I'd suspect that the heat load from the tracing is condensing steam faster than the supply can deliver it. You could try increasing the steam supply pressure.

 

[PAN]

roker,
I do not recommend carbon steel tube as tracing material, because carbon steel tube has thin wall without corrosion allowance. Stainless steel tube should be a better choice to avoid corrosion.

ulpain,
What are the size of pipelines? Carbon steel pipe size 1/2 or 3/4 inch may be an option for tracing.